Dr Clements, an eighth- generation Tasmanian himself, learnt of his family's involvement in the Black War.

His great-great-great-great-great grandfather had been attacked five times and lost two servants to Aborigines.

His ancestor later took part in an ambush.

"Obviously I'm not proud of what they did, but I'm interested in why this happened," Dr Clements said.

"We're kidding ourselves if we think this wouldn't have been us."

Writing the book, which is distilled from his PhD with the University of Tasmania, provided plenty of opportunities for Dr Clements.

While he maintained an open mind before undertaking his research his views were challenged.

"I went in assuming it was genocide, and that the Aborigines were relatively helpless.

"I've changed my mind in both cases, which surprised me, and will probably upset some people," Dr Clements said.

The Black War outlines his reasoning: "Whatever word we use, we must at least acknowledge that the attitudes and circumstances that provoked colonists to kill natives in Tasmania were very different from those typically associated with genocide".

Dr Clements knows the book is likely to provoke a strong reaction and said he sadly suspects there will be some who will be upset by his approach.

He has not consulted with any Aboriginal groups, relying instead on years of sound and informed research.

Reading and writing about the enslavement of Aboriginal women and children by sealers in the final chapter of the book was especially difficult, Dr Clements said.

"The horrors of the Black War were only possible because Aborigines and colonists dehumanised each other," Dr Clements said.

"We can never allow such things to happen again."

The Black War will be launched at Fullers in Launceston on May 2 at 6pm. Reservations are essential. To book, email launceston@fullersbookshop.com. au